功率谱密度函数的构建及在重力场元计算中的应用  

Construction of Power Spectral Density Functions and Application in Computation of Gravity Functions

作　　者：陈欣[1,2] 翟国君[2] 暴景阳[1] 欧阳永忠[2] 陆秀平[2] 吴太旗[2] 邓凯亮[2] 

机构地区：[1]海军大连舰艇学院海洋测绘系,辽宁大连116018 [2]海军海洋测绘研究所,天津300061

出　　处：《海洋测绘》2016年第1期6-10,共5页Hydrographic Surveying and Charting

基　　金：国家自然科学基金(41474012;41374018);国家重大科学仪器设备开发专项(2011YQ12004503);国防973计划(613219)

摘　　要：应用输入输出法逼近局部重力场的关键在于构建有效反映局部重力场特征的功率谱密度函数模型、利用"间接法",基于Moritz协方差模型、Tscherning/Rapp协方差模型和Moritz两分量模型分别构建对应的功率谱密度函数模型,并采用非线性最小二乘法在EGM2008模型的基础上拟合了模型系数。拟合结果表明:在2倍相关长度的相关距离内,Moritz两分量模型求得的理论协方差值与经验协方差值的符合度最好。设计了以EGM2008模型重力异常为基础数据,计算大地水准面高的仿真实验。结果表明:三种模型中,Moritz两分量模型的计算结果精度最高,同传统Stokes方法的计算结果精度相当,与拟合的理论协方差曲线图所反映的结果一致。Construction of power spectral density functions which can reflect the characteristics of local gravity field effectively is the crux of using Input-Output method to approximate the earth gravity field. Based on the Moritz covariance model, Tscherning/Rapp covariance model and Moritz two-component covariance model, the corresponding power spectral density functions are constructed, by using the indirect method. Also, the model coefficients are fitted by using the non-linear least-square method under the EGM2008 model, and the results show that the theoretical covariance which is calculated by the Moritz two-component covariance mode/ is consistent with the experiential covariance, when the correlation distance is twice the correlation length. The experiments using gravity anomalies based on the EGM2008 to determine the geoid is designed.The results show that the geoid calculated by Moritz two-component model has the highest precision within three models, nearly equivalent to the Stokes method, which is consistent with theoretical covariance graph.

关 键 词：大地水准面 重力异常 功率谱密度函数 协方差函数 EGM2008模型 输入输出法 

分 类 号：P223[天文地球—大地测量学与测量工程]